Miss Saigon’s running time may be just shy of three hours – but sitting in the audience, it feels like a matter of minutes.

It is so hugely engrossing, you are `there’ in the action from the off and it delivers a pace I’ve seldom seen in musical theatre.

The hit show is at Sunderland Empire from October 24 to November 17 and, having watched it a few weeks ago in Edinburgh, I now rate it in my top five musical productions of all time. Be warned, too, that a box of tissues may just be needed to wipe away those tears at the end.

Miss Saigon tells the story of the last days of the Vietnam War. Seventeen-year-old Kim is forced to work in a Saigon bar run by a notorious character known as the Engineer.

There she meets and falls in love with an American GI named Chris, but they are torn apart by the fall of Saigon.

Miss Saigon. Sooha Kim as Kim and Ashley Gilmour as Chris.

For three years Kim goes on an epic journey of survival to find her way back to Chris, who has no idea he’s fathered a son.

This current production is both outstanding and astounding. It has you in the palm of its hands from beginning to end, bolstered by a magnificent set, superb direction and that wonderful score by Claude-Michel Schönberg with lyrics by Richard Maltby Jr and Alain Boublil.

Miss Saigon. Sooha Kim as Kim.

All the action centres around the three main characters of Kim (Sooha Kim), Chris (Ashley Gilmour) and The Engineer (Red Concepion), and I met the latter two backstage in Edinburgh.

“I like to think of The Engineer as a cockroach,” Red, who is Filipino born and bred, tells me. “You know how they say cockroaches will survive everything, well that’s how he is. He’ll just find a way to survive. If he can come out on top, he’ll do it. If that mean’s he is going to deceive or manipulate or debase himself, he’ll do it.

Miss Saigon, which is coming to Sunderland Empire. Red Concepion as The Engineer. (Image: Johan Perrson)

“But he’s also very charismatic, and that’s one of his many tools. He’s a wolf in sheep’s clothing. He’ll show you what he thinks is best so he can get the most out of the situation.

“It’s a very fun role but also very dark. With my interpretation of him, he uses his charm a lot. He’s a `good’ baddie, people are very drawn to him.

“He makes you forget he is this horrible person. It was a case of striking that fine balance. You don’t want him to be too loveable but you don’t want him to be hated either.

“Miss Saigon is about these three people who are dealing with the after effects of the Vietnam War. The Engineer learned survival skills that are less than savoury. But he’s just a product of his time.”

Red excels in the role. He’s captivating and does achieve that likeability to the character – which is no mean feat.

Miss Saigon, which is coming to Sunderland Empire.

“I think it’s very timely that we are doing this. People need to be reminded of the horrors of war and what kind of people come out of that,” he says.

“The Engineer is one of the by-products of being in a war, plus the lengths that Kim goes to protect this child that she got because of this war.

“It’s good that people can be reminded of that as we are living in a very tumultuous time in the world’s history.

“At the very heart of it, it is also a love story, and people get drawn to that. There’s so much raw truth in the show.”

Fellow cast member Ashley Gilmour is no stranger to Miss Saigon. “I was in the original West End revival in 2014,” he reveals. “It was actually my first big job after drama school, which was amazing.

Miss Saigon, which is coming to Sunderland Empire. Ashley Gilnour as Chris.

“I’d spent six months auditioning for different shows, but what an amazing first job. You work so hard for those two and a half hours in the show and it’s so rewarding to see the story you have told and the work you have done on the stage is enough to affect people and make them want to stand up and cheer and clap. That’s a really special feeling.”

I ask Ashley how the show has changed since 2014. “The show I did in the West End was taken to Broadway, improved upon with bits added to it, and that is the show you are seeing here.

Miss Saigon, which is coming to Sunderland Empire.

“You find a lot of touring shows are the condensed version of what they were in the West End but this one is the full show.

“It’s so amazing to be in a show like this where every element of the set, the lighting, the sound, is top quality. This is a Broadway show on tour basically.

“Miss Saigon will always be relevant to what’s happening in the world. There’s always going to be war, there’s always going to be families torn apart and mass exoduses from countries.

“That’s why it is important for the stories of those people to be told and to be viewed by an audience.”